Load sensitive friction type load brakes for hoists in which braking discs rotate in engagement with friction discs only during lowering operation of the hoist to restrain the lowering speed and thereby enable motor control of the load are known as "Weston" brakes and are well-known. Load sensitive friction load brakes are commonly of two types. One of these is an in-line brake arrangement in which the motor drive shaft, the shaft about which the friction plates rotate, and the drum axis of rotation are in alignment and rotate in the same direction during a raising or lowering operation of the hoist. Another type of load sensitive friction load brake uses a counter-shaft arrangement in which a gear drive is provided from the motor/drum drive shaft to one side of the drive shaft drum and the friction discs rotate about a separate shaft to one side of and parallel to the motor/drum drive shaft. The brake restraining force is provided through a second gear connection back to the motor/drum drive shaft.
The counter-shaft type of load sensitive load brake presents the problem of occupying a large amount of space. Such bulkiness is particularly undesirable in hoists which occupy a large amount of space due to use of a planetary or fixed compound differential reduction gear drive in addition to the regular motor and hoist brake. In-line types of load sensitive load brakes are also undesirable where large gear drives, such as planetary or fixed compound differential gear drives are used, since use of an in-line load brake requires placing the motor, the gear drive, as well as the load brake, at the same end of the hoist drum. This results in a highly unbalanced hoist apparatus which presents undesirable problems in suspending the hoist from its overhead support. The present invention is an improvement in load sensitive load brakes which eliminates the problems described above in both the counter-shaft and in-line type of load brakes.